With the 2013 tennis season in the past, it's time to dole out our annual awards. Look for the winners—for better or worse—throughout this week on TENNIS.com. (To see what's been unveiled thus far, click here.)

Samantha Stosur: It took a long time for the Aussie’s singles window to open; has it already begun to close? After a decade spent deep in the third tier of singles players—she finished 2008 ranked No. 52—Stosur, a longtime doubles specialist, finally cracked the Top 10 three years ago. By the end of 2011, at age 27, she was the U.S. Open champion. While she didn’t do anything as spectacular as that in 2012, Sam was solid enough to finish the season No. 9.

That’s not to say Stosur didn’t have her share of bad losses even in the good years, including multiple early-round exits at her home Slam in Melbourne. But her downs were balanced out by her ups, which typically came when she moved to clay in the spring. This year, Stosur got off to her usual slow start Down Under; she lost in the first round in Brisbane and Sydney, and the second round at the Aussie Open. This time, though, her body wasn’t ready for the turn to dirt. A calf injury forced Stosur to withdraw from Indian Wells and retire in Charleston. First-round losses followed in Stuttgart and Madrid.

Stosur showed periodic signs of life through the summer—a title in Carlsbad, a quarterfinal in Rome—but her most notable match was, unfortunately, a stunning first-round loss to 17-year-old Victoria Duval at the U.S. Open. Stosur admitted that breaking up with her coach of six years, David Taylor, just nine days before the tournament hadn’t helped. By the fall, she was down to No. 20 in the rankings.

Yet all does not appear lost for Sam. Post-Taylor, she finished the year on a high note, winning another title in Osaka, and reaching the finals in her last two tournaments, in Moscow and Sofia. Is a strong start in Oz around the corner? Is the window, at 29, still open? For now, Stosur may just be happy to leave 2013 behind.

*****

Janko Tipsarevic: There may be two lessons to be learned from the recent rise and current fall of Janko Tipsarevic. (1) There’s a statute of limitations on inspiration. (2) Heel injuries are for real.

Like his fellow Serb Novak Djokovic, Tipsy’s world was turned upside-down, in a good way, by their Davis Cup win in 2010. After spending years ranked in the 40s and 50s, he began a slow but steady ascent in 2011. By season’s end, he had cracked the Top 10, a place he would remain until May of 2013. At age 28, the former journeyman had established himself among the game’s elite.

Or so it seemed. Tipsarevic’s decline really began in January, and it was as swift as it was surprising. At first, he appeared ready to pick up where he had left off: He opened the season by winning the title in Chennai, then reached the fourth round at the Australian Open, a run that included an impressive win over hometown favorite Lleyton Hewitt, followed by two hard-fought, five-set victories. In his next match, though, against Nicolas Almagro, Tipsarevic had to retire in the second set.

“I don’t know how I managed to do it,” a disgusted and perplexed Tipsy said after that match, “but I completely screwed up my left heel.”

The fact that the injury was severe enough to force him from the tournament, but not severe enough to force him from the tour entirely, may have been a double misfortune for Tipsarevic. His results immediately tanked—he lost in the first round in five of his next six events—but the heel never healed. Tipsarevic would finish the year with 14 first-round losses, a 20-24 record, and a ranking back down in his old, pre-2011 neighborhood, at No. 36.

And that wasn’t the worst of it. After all of those defeats, Tipsarevic was unable to play the Davis Cup final for Serbia in November because of his now-chronic heel problem. The team lost both of the singles ties he would have played, and with them a chance at their second Cup. Tipsy will have to look elsewhere for the inspiration to rise again in 2013.